Transmission cables may be used to transmit data between workstations, mainframes and other computers, as well as provide data connections to mass storage devices and other peripheral devices. Data may be transferred using a variety of transmission cable technologies, including multimode optical fiber cables, single mode optical fiber cables, and copper cables (e.g., twinax and coax copper cables). Standard communications modules have been developed to transition between different transfer media and the electronic components inside a computer or peripheral device. Among the common communication modules are transmitter modules, receiver modules, and transceiver modules.
A communications module produces a standardized output to the host system in accordance with prescribed protocols, regardless of the medium (e.g., optical fiber or copper) through which the data is transmitted or received. For example, an optoelectronics transceiver module enables bidirectional data transmission between an electrical interface and an optical data link. A copper transceiver module, on the other hand, enables bidirectional data transmission between two electrical devices.
A communications module typically plugs into a cage that extends out of the rear panel of a host device (e.g., a computer or a peripheral device). The cage connects the transceiver module to a motherboard or circuit card in the computer or peripheral device.